Traditionally, there is a known electromagnetic clutch including a pole body having an exciting coil, a rotor that is located at a position facing the pole body and is integrally rotatable with a rotating shaft, and an armature slidable in the axial direction of the rotating shaft, wherein when the exciting coil is in an excited state, the armature is pressed against the rotor by a magnetic attraction force to transmit a rotating torque (see Patent Literature 1).